Oki ES9160, Maintenance Manual

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ES9160 MFP / ES9170 MFP © 2012 OKI DATA CORPORATION All rights reserved
SETTING / ADJUSTMENT
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6.4 Image Quality Adjustment (Copying Function)
6.4.1 Automatic gamma adjustment
When the reproduction of gradation is not appropriate, it can be corrected by performing this automatic
gamma adjustment. At the parts replacement and in case the gradation reproduction of the image is not
satisfactory, make this adjustment as described below.
(1) When unpacking or any of the following parts has been replaced, be sure to make this
adjustment:
• Photoconductive drum
• Developer material • Laser optical unit
• Transfer roller • Drum cleaning blade
• Main charger grid • SRAM board
(2) Be sure to perform this adjustment whenever HDD data are cleared.
<Procedure>
(1) While pressing [0] and [5] simultaneously, turn the power ON.
→
Adjustment Mode
(2) Select the A4/LT drawer. Key in “10” and press the [FAX] button to print a “Patch chart for gamma
adjustment”.
(3) Place the patch chart for adjustment printed in step (2) face down on the original glass. Place the
chart aligning its black side of the gradation pattern against the original scale.
(4) Key in a code and press the [START] button.
(5) If the adjustment is finished properly, press [OK] to have its results reflected.
(To cancel the reflection of adjustment results, press the [CANCEL] button.)
In the case of an abnormal ending, “ADJUSTMENT ERROR” is shown.
Press the [CANCEL] button to clear the error display. When it is cleared, the control panel display
will return to the ready state. Then, check if the patch chart on the original glass is placed in the
wrong direction or if it is placed inclined on the original glass, and then repeat step (3) and
afterward.
Code
Item to be
adjusted
Contents
05-7165 Automatic gamma
adjustment When the reproduction of gradation is not appropriate, it can be
corrected by performing this automatic gamma adjustment.